/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/

/**
 * \file pkcs11.c
 *
 * \brief Wrapper for PKCS#11 library libpkcs11-helper
 *
 * \author Adriaan de Jong <dejong@fox-it.com>
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */

#include "tls/pkcs11.h"

#if defined(MBEDTLS_PKCS11_C)

#include "tls/md.h"
#include "tls/oid.h"
#include "tls/x509_crt.h"

#if defined(MBEDTLS_PLATFORM_C)
#include "tls/platform.h"
#else
#include <stdlib.h>
#define mbedtls_calloc    calloc
#define mbedtls_free       free
#endif

#include <string.h>

void mbedtls_pkcs11_init(mbedtls_pkcs11_context *ctx)
{
	memset(ctx, 0, sizeof(mbedtls_pkcs11_context));
}

int mbedtls_pkcs11_x509_cert_bind(mbedtls_x509_crt *cert, pkcs11h_certificate_t pkcs11_cert)
{
	int ret = 1;
	unsigned char *cert_blob = NULL;
	size_t cert_blob_size = 0;

	if (cert == NULL) {
		ret = 2;
		goto cleanup;
	}

	if (pkcs11h_certificate_getCertificateBlob(pkcs11_cert, NULL, &cert_blob_size) != CKR_OK) {
		ret = 3;
		goto cleanup;
	}

	cert_blob = mbedtls_calloc(1, cert_blob_size);
	if (NULL == cert_blob) {
		ret = 4;
		goto cleanup;
	}

	if (pkcs11h_certificate_getCertificateBlob(pkcs11_cert, cert_blob, &cert_blob_size) != CKR_OK) {
		ret = 5;
		goto cleanup;
	}

	if (0 != mbedtls_x509_crt_parse(cert, cert_blob, cert_blob_size)) {
		ret = 6;
		goto cleanup;
	}

	ret = 0;

cleanup:
	if (NULL != cert_blob) {
		mbedtls_free(cert_blob);
	}

	return (ret);
}

int mbedtls_pkcs11_priv_key_bind(mbedtls_pkcs11_context *priv_key, pkcs11h_certificate_t pkcs11_cert)
{
	int ret = 1;
	mbedtls_x509_crt cert;

	mbedtls_x509_crt_init(&cert);

	if (priv_key == NULL) {
		goto cleanup;
	}

	if (0 != mbedtls_pkcs11_x509_cert_bind(&cert, pkcs11_cert)) {
		goto cleanup;
	}

	priv_key->len = mbedtls_pk_get_len(&cert.pk);
	priv_key->pkcs11h_cert = pkcs11_cert;

	ret = 0;

cleanup:
	mbedtls_x509_crt_free(&cert);

	return (ret);
}

void mbedtls_pkcs11_priv_key_free(mbedtls_pkcs11_context *priv_key)
{
	if (NULL != priv_key) {
		pkcs11h_certificate_freeCertificate(priv_key->pkcs11h_cert);
	}
}

int mbedtls_pkcs11_decrypt(mbedtls_pkcs11_context *ctx, int mode, size_t *olen, const unsigned char *input, unsigned char *output, size_t output_max_len)
{
	size_t input_len, output_len;

	if (NULL == ctx) {
		return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
	}

	if (MBEDTLS_RSA_PRIVATE != mode) {
		return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
	}

	output_len = input_len = ctx->len;

	if (input_len < 16 || input_len > output_max_len) {
		return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
	}

	/* Determine size of output buffer */
	if (pkcs11h_certificate_decryptAny(ctx->pkcs11h_cert, CKM_RSA_PKCS, input, input_len, NULL, &output_len) != CKR_OK) {
		return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
	}

	if (output_len > output_max_len) {
		return (MBEDTLS_ERR_RSA_OUTPUT_TOO_LARGE);
	}

	if (pkcs11h_certificate_decryptAny(ctx->pkcs11h_cert, CKM_RSA_PKCS, input, input_len, output, &output_len) != CKR_OK) {
		return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
	}
	*olen = output_len;
	return (0);
}

int mbedtls_pkcs11_sign(mbedtls_pkcs11_context *ctx, int mode, mbedtls_md_type_t md_alg, unsigned int hashlen, const unsigned char *hash, unsigned char *sig)
{
	size_t sig_len = 0, asn_len = 0, oid_size = 0;
	unsigned char *p = sig;
	const char *oid;

	if (NULL == ctx) {
		return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
	}

	if (MBEDTLS_RSA_PRIVATE != mode) {
		return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
	}

	if (md_alg != MBEDTLS_MD_NONE) {
		const mbedtls_md_info_t *md_info = mbedtls_md_info_from_type(md_alg);
		if (md_info == NULL) {
			return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
		}

		if (mbedtls_oid_get_oid_by_md(md_alg, &oid, &oid_size) != 0) {
			return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
		}

		hashlen = mbedtls_md_get_size(md_info);
		asn_len = 10 + oid_size;
	}

	sig_len = ctx->len;
	if (hashlen > sig_len || asn_len > sig_len || hashlen + asn_len > sig_len) {
		return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
	}

	if (md_alg != MBEDTLS_MD_NONE) {
		/*
		 * DigestInfo ::= SEQUENCE {
		 *   digestAlgorithm DigestAlgorithmIdentifier,
		 *   digest Digest }
		 *
		 * DigestAlgorithmIdentifier ::= AlgorithmIdentifier
		 *
		 * Digest ::= OCTET STRING
		 */
		*p++ = MBEDTLS_ASN1_SEQUENCE | MBEDTLS_ASN1_CONSTRUCTED;
		*p++ = (unsigned char)(0x08 + oid_size + hashlen);
		*p++ = MBEDTLS_ASN1_SEQUENCE | MBEDTLS_ASN1_CONSTRUCTED;
		*p++ = (unsigned char)(0x04 + oid_size);
		*p++ = MBEDTLS_ASN1_OID;
		*p++ = oid_size & 0xFF;
		memcpy(p, oid, oid_size);
		p += oid_size;
		*p++ = MBEDTLS_ASN1_NULL;
		*p++ = 0x00;
		*p++ = MBEDTLS_ASN1_OCTET_STRING;
		*p++ = hashlen;
	}

	memcpy(p, hash, hashlen);

	if (pkcs11h_certificate_signAny(ctx->pkcs11h_cert, CKM_RSA_PKCS, sig, asn_len + hashlen, sig, &sig_len) != CKR_OK) {
		return (MBEDTLS_ERR_RSA_BAD_INPUT_DATA);
	}

	return (0);
}

#endif							/* defined(MBEDTLS_PKCS11_C) */
